172 ON CUSCUTA GKOXOVII. 



before germination. Fig. 2 is the root end of a seedling 2 inches 

 long, and hence the rhizoids are much further developed. Fig. 5 

 illustrates one of the most interesting things in my study of the 

 plant, and one that I could not find mentioned by any observer, 

 viz., a method by which the plant cut itself off from normal 

 nutrition. Having reached some suitable host — a twig of 

 Forsythia viridissima in this case — it twines around it like a 

 tendril, by two or three coils, and in coiling contracts so as to 

 draw itself nearer the host. This contraction, if the seedling is 

 not too deeply rooted, or too slack between the soil and the sup- 

 port, pulls the roots from the earth and leaves the plant — a 

 parasite by suicide — with roots at varying distances above the soil, 

 \ of an inch being perhaps the highest I observed. If the plant 

 is not uprooted in this manner or by the lengthening of the 

 internode of the host to which it is attached, as sometimes 

 happens, the lower part of the stem dies, and the connection is 

 thus severed with the absorbing root, not, however, until the 

 enlarged portion of the stem has been drained of its nourishment 

 or the plant has reached some other supply. All the plants that 

 germinated earliest, of those we studied, hung themselves ; the 

 later ones — those washed deeper into the soil — died at base. Our 

 gardener, noticing the hanging ones, said, " Those are not plants ; 

 they crawl up sticks like an inch- worm." These germinating 

 plants are white below, but yellowish-green at summit, suggesting 

 that the dodder, even in its degeneracy, has some chlorophyll, and 

 may elaborate food for a short time. The amount of nourishment 

 stored in the embryo hardly seems sutficient to enable the seedling 

 to produce such a length of stem before reaching a host, as is 

 done by some. Other things, too, indicate ability to assimilate, 

 such as the greenness of buds and branches, for some time after 

 they appear. This colouring matter is removed by alcohol. 



To illustrate the ra])idity of growth after germination, I give 

 the statistics of a single plant, grown in my own room under a 

 bell-jar, in circumstances perhaps not the most favourable, as there 

 was much variation in temperature, especially at night. The 

 seeds were collected out of doors on some alder twigs, and sowed 

 immediately, February 29. The first plantlet appeared at the 

 surface of the soil, March 20, and twenty-four hours later, at 



